Hydraulic jack.



G. NIGOLAI. HYDRAULIC JACK.

APPLICATION FILED SEPT. 7, 1911.

1,022,865. Patented Apr. 9, 1912.

cnLuMnlA PLANOGRAPII tin-WASHINGTON n n.

GUSTAV NICOLAI, 0F HONOLULU, TERRITORY OF HAWAII.

HYDRAULIC JACK.

Specification of Letters Patent.

Patented Apr. 9, 1912.

Application filed September '7, 1911. Serial No. 648,048.

To all whom it may concern:

Be it known that I, GUSTAV NICOLAI, a citizen of the German Empire,residing at Honolulu, county of Honolulu, Territory of Hawaii, haveinvented certain new and use; ful Improvements in Hydraulic Jacks; and Ido hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to hydraulic jacks, and particularly to thesealing of the joint between the ram and the Wall of the cylinder of thejack.

In hydraulic jacks as applied to sugar cane mills for obtaining auniform pressure on the rolls, it is customary to employ a singleleather crimp or rubber crimp for sealing the joint between the ram andthe cylinder. The crimp is removably secured to the end of the ram bymeans of a washer and bolt. High pressures (usually from 4000 to 5000pounds per square inch) are maintained in the jacks by means of anaccumulator and pump. The pressure on the rolls immediately fallswhenthe crimp in a jack gives out, and the mill has to be shut downuntil the defective crimp has been replaced, causing an annoying andexpensive delay.

The principal object of this invention is to eliminate such delays.

The invention contemplates the employment of a plurality of crimps ineach jack, such that when the first crimp gives out the next crimp willseal the joint. It also contemplates means for automatically notifyingthe engineer in charge that a crimp has failed, so that it can bereplaced after the days run, the next crimp acting in the illterval,thus avoiding an immediate shut down.

In carrying out the invention, two or more crimps are secured to the endof the ram by a bolt with the usual washer for the first crimp and othersuitably shaped washers interposed between the crimps. The ram isprovided with a valve connected by a pas-' sage with the annular spacebetweenthe first two crimps, such that the valve is only operated whenthe first crimp either gives out or leaks sufiiciently to needreplacing. This valve may give warning in several ways, such as bysimply emitting a small stream of water, or preferably by closing thecircuit of an electric bell.

While the invention is described as applied to hydraulic jacks, it isobvious that it may be applied and used with hydraulic plungers of pumpsor the like.

In the accompanying drawings, forming a part of this specification,Figure 1 repre sents a sectional view of a hydraulic jack embodying myinvention. Fig. 2 is a detail 011 a larger scale of the alarm valve.

Referring to the drawings, 1 represents the cylinder of the hydraulicjack, which is usually a steel casting provided with a port 2 to whichthe pipe to the accumulator is at tached in a well known manner. The ram3 of cast iron or steel is adapted to slide freely in the cylinder 1.The crimps t and 5 of leather or other suitable material are providedwith washers 6 and 7 respectively and are secured to the end of the ram3 by the bolt 8. An annular space 9 is formed bet-ween the peripheryofthe washer 6, the

wall of the cylinder 1, and the crimps t and 5. This annular space 9 isconnected by the passage. 10 in the washer 6, a hole 11 in the crimp t,and by the passage 12 in the ram 3,

with a valve chamber 13 formed in the end of the plug 14: screwed into athreaded hole in the portion of the ram 3 outside of the cylinder 1.

15 is a lead or other Washer.

The plug 14: has a valve seat 16 adapted to seat the valve 17. The valvestem 18 is provided with a passage 19 which is closed when the valve isseated. The valve is normally held open by the spring 20 which engagesthe end of the valve stem 18, and in this position the passage 19connects the valve chamber 13 with the atmosphere. When the valve 17 isseated the spring 20 is pushed by the valve stem 18 so that it makescont-act with the spring 21. Both springs 20 and 21 are insulated fromthe ram 3 to which they are attached. The springs 20 and 21 areconnected by the wires 22 with a bell 23, a battery 24 and a switch 25,in a wellknown manner, such that when the switch 25 is closed the bell23 will ring while the springs 20 and 21 are in contact.

In operation, the water is admitted through the port 2 and the crimp 5seals the joint between the washer 6 and the cylinder 1. The water whichleaks past the crimp 5 into the annular space 9 is forced through thepassage 10, hole 11 and passage 12 into the valve chamber 13 and thencethrough the passage 19 and is emitted from the end of the valve stem 18.Then the leakage is sufficiently large, as by the failure of the crimp5, the water rushes into the chamber 13 faster than it can flow throughthe small passage 19 and the valve 17 is forced against the seat 16against the action of the sprin 20. In this position the passage 19 hasbeen closed and the spring 20 has made contact with the spring 21causing the bell 23 to ring until the switch 25 is opened. hen the crimp5 fails the crimp t seals the joint between the ram 3 and the cylinder1, and permits of the continued use of the ack until such time as themill shuts down. As the engineer has been notified in the mannerdescribed of the failure of crimp 5, this crimp is replaced before againstarting up the mill.

I claim:

1. In a hydraulic jack, the combination with a ram having two or morecrimps, of means to indicate automatically the failure of one of saidcrimps, said means comprising an outlet passage through the ram, and asignal device in connection with said passage.

2. In a hydraulic jack, a cylinder, a ram provided with two crimps witha washer interposed, a valve, a passage connecting the annular spacebetween said crimps with the chamber of the valve, and a passage in thevalve stem, substantially as described.

3. In a hydraulic jack, a cylinder, a ram provided with two crimps withan interposed Washer, a valve, a passage connecting the annular spacebetween said crimps with the chamber of the valve, and the stem of saidvalve adapted to operate the contacts of an electrical alarm circuit,substantially as described.

In testimony whereof I affix my signature, in presence of two witnesses.

GUSTAV NICOLAI.

WVitnesses R0131. J. PRATT, CHAS. L. SEYBOLT.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

